Other people's plans, own problems

If Eneas had been given the choice, despite the fact that a little less than half of the Saitan fleet was still deployed by that system, he would have withdrawn his troops, and would have waited for another opportunity later, once the enemy line had been stretched to attack again.

However, an officer of the imperial navy devised a plan in case this situation arose: the enemy attack would only be with a part of its global forces.

It's not that the plan was bad; it had a good chance of working. What happened was that it was a risk in case the reinforcements that Eneas had predicted arrived. If the battle was not resolved quickly, they could encounter a second wave.